Macrocyclic lactam prokinetic agents

ABSTRACT

Macrocylic lactam compounds of formula (I) ##STR1## and pharmaceutically acceptable salts thereof, wherein A is selected from ##STR2## also disclosed are synthetic processes and intermediates useful in the preparation of the compounds of the invention, as well as compositions containing the same and methods for their use in stimulating contractile motion of the gastrointestinal tract.

This application is a divisional of U.S. Ser. No. 08/108,659, filed Mar.30, 1992, pending which is a continuation-in-part of U.S. Ser. No.07/682,836, filed on Apr. 9, 1991, now abandoned.

TECHNICAL FIELD

This invention relates to novel macrocyclic lactam derivatives oferythromycins A, B, C and D and pharmaceutical compositions containingthese compounds, as well as the use thereof in treating gastrointestinaldisorders and in facilitating the placement of diagnostic andtherapeutic instrumentation into the proximal small intestine. Theinvention also relates to processes for preparing these compounds andsynthetic intermediates employed therein.

BACKGROUND OF THE INVENTION

The primary function of the alimentary or gastrointestinal (GI) tract isto provide the body with a balanced supply of water, electrolytes andnutrients. In order for this to be achieved, food must be moved alongthe GI tract at an appropriate rate for digestion, absorption andsecretion to take place. Food is normally transported through the GItract in a well-coordinated manner by propulsive movements which aremediated by clusters of smooth muscle contractions known as migratingmyoelectric complexes, in a process commonly referred to as peristalsis.

Defects in the normal motility pattern can lead to the development ofchronic, painful and debilitating disorders. For example, an incompetentor weak lower esophageal sphincter may result in frequent reflux ofingested food from the stomach into the esophagus which may lead toesophagitis. Prokinetic agents (also called motility-enhancing agents)are useful in treating reflux esophagitis because they (a) increase thepressure of the lower esophageal sphincter, thereby inhibiting reflux;(b) increase the force of esophageal peristalsis to facilitate clearanceof food from the esophagus into the stomach; and (c) increase gastricemptying, thereby further decreasing the mass available for reflux.

There is a need, however, for improved prokinetic agents in thetreatment of this disorder. Presently used cholinergic drugs such asbethanechol and dopamine receptor blocking agents such as metoclopramidemay exhibit serious disadvantages. Bethanechol, for example, should beavoided by elderly patients while metoclopramide has a narrowtherapeutic index, pronounced central nervous system (CNS) side effectsand is known to stimulate prolactin release.

Patients suffering from other GI motility-related disorders such asdelayed gastric emptying, diabetic gastroparesis, anorexia, gall bladderstasis, surgically induced adynamic ileus and chronic constipation(colonic inertia) may also benefit from treatment with prokineticagents. In addition, prokinetic agents can aid in the placement ofdiagnostic and therapeutic instrumentation, such as during the insertionof enteral feeding tubes into the proximal small intestine.

Another, less common but very painful and disruptive GI motilitydisorder is chronic intestinal pseudoobstruction. Patients who areseverely afflicted with this problem cannot tolerate oral feedings andrequire total parenteral nutrition. Metochlopramide and bethanecholineare also used in the treatment of this disorder but often withdisappointing results. Prokinetic agents could not only be useful inalleviating the distress associated with this disorder, but also insevere cases could be used to facilitate treatment by decompression ofthe upper GI tract by nasogastric tubal aspiration. Increased gastricmotility brought about by the use of a prokinetic agent has been shownto facilitate the placement of the necessary tubes into the intestine.

Macrocyclic lactone (macrolide) prokinetic agents are known. Forexample, J. S. Gidda et al., in European Patent Application No. 0349100,published Jan. 3, 1990, disclose 12-membered macrolides for use asgastrointestinal motility enhancers. S. Omura and Z. Itoh, in U.S. Pat.No. 4,677,097, issued Jun. 30, 1987, European Application No. 215,355,published Mar. 25, 1987, and European Application No. 213,617, publishedMar. 11, 1987, disclose derivatives of erythromycins A, B, C and D whichare useful as stimulants of digestive tract contractile motion. However,the compounds of these references are distinct from those of the presentinvention, in which novel lactam derivatives of the erythromycins aredisclosed which possess an unexpected degree of prokinetic activity.

SUMMARY OF THE INVENTION

In one aspect of the present invention are provided macrocylic lactamprokinetic agents of formula (I) ##STR3## and pharmaceuticallyacceptable salts thereof wherein the dotted line is an optional bond. Informula (I), A is selected from ##STR4## where a wavy line represents abond having either steric orientation.

R¹ and R² in formula (I) may independently be selected from hydrogen,loweralkyl, halo-substituted loweralkyl, cyano-substituted loweralkyl,hydroxy-substituted loweralkyl, loweralkenyl, loweralkynyl, lowercycloalkyl, lower cycloalkylmethyl and benzyl.

R³ in formula (I) may be absent or, if present, selected fromloweralkyl, loweralkenyl, loweralkynyl and benzyl and accompanied by apharmaceutically acceptable counterion so as to form a quaternaryammonium salt.

R⁴ in formulae (I) and (III) may be hydrogen or, taken together with R⁶,may form an ether bridge.

R⁵ in formula (I) may be --OH, or --OR¹⁰, wherein R¹⁰ is selected fromloweralkyl, loweralkanoyl and --S(O)₂ CH₃, or taken together with R⁶ andthe carbons to which they are attached, may form a cyclic carbonate.

R⁶ in formula (I) may be hydrogen, --OH, or --OR¹¹ wherein R¹¹ isselected from loweralkyl, loweralkanoyl and --S(O)₂ CH₃ ; or, takentogether with R⁴, may form an ether bridge; or, taken together with R⁵and the carbons to which they are attached, may form a cyclic carbonate.

R⁷ in formula (I) may be either hydrogen or methyl.

R⁸ in formula (I) may be hydrogen or loweralkyl.

R⁹ in formula (I) may be hydrogen or hydroxy.

In another aspect of the present invention are provided syntheticprocesses for preparing the compounds of the invention, as well as novelintermediates of formulae (V) and (VI) ##STR5## useful therein whereinR⁶ is --OH or hydrogen, R⁷ is hydrogen or methyl, R⁸ is hydrogen orloweralkyl and R⁹ is hydrogen or hydroxyl. The lactam compounds of theinvention may be prepared directly from such intermediates, as byinducing ring closure of the amine alcohol of formula (V) or by anepoxide opening and spontaneous cyclization of the epoxide of formula(VI). Alternatively, the epoxide intermediate may first be converted toan azido alcohol and then reduced to the above amine alcohol before ringclosure is induced.

In a further aspect of the present invention are provided pharmaceuticalcompositions for stimulating contractile motion of the gastrointestinaltract comprising a therapeutically effective amount of a compound of theinvention and a pharmaceutically acceptable carrier.

In yet another aspect of the present invention is provided a method oftreating disorders characterized by impaired gastrointestinal motilitysuch as esophageal reflux, diabetic gastroparesis, pediatricgastroparesis, postoperative paralytic ileus, intestinalpseudoobstruction, gallbladder stasis, anorexia, gastritis, emesis andchronic constipation, comprising administering to a human or lowermammal in need of such treatment a therapeutically effective amount of acompound of the invention. In a related aspect, the present inventionprovides a method of facilitating the placement of diagnostic andtherapeutic instrumentation, such as enteral feeding tubes, into theproximal small intestine comprising administering to a human or lowermammal in need of such treatment a therapeutically effective amount ofan inventive compound.

DETAILED DESCRIPTION OF THE INVENTION

The present invention comprises novel compounds of formula (I) and thepharmaceutically acceptable salts thereof which are gastrointestinalprokinetic agents. The compounds of the present invention did notexhibit antibacterial activity in in vitro screening assays. Thesecompounds are synthetic lactam derivatives of erythromycins A through D;accordingly, substituents R⁶ and R⁷ of the formulae herein are initiallydetermined, as shown below, by the particular erythromycin used asstarting material:

    ______________________________________                                        Erythromycin  Resulting R.sup.6                                                                        Resulting R.sup.7                                    ______________________________________                                        A             --OH       methyl                                               B             hydrogen   methyl                                               C             --OH       hydrogen                                             D             hydrogen   hydrogen                                             ______________________________________                                    

However, such lactams may be further derivatized, using well-knownsynthetic methodology, to obtain compounds of the invention having othersubstituents R⁶ as well.

One class of compounds of the present invention, formed when A offormula (I) is a group of formula (II), may be represented by theformula ##STR6##

Another class of compounds of the invention, formed when A is a group offormula (III) in which R⁴ is hydrogen, may be represented by the formula##STR7## wherein, as elsewhere throughout this application, a wavy linerepresents a bond having either steric orientation.

A corresponding subclass of compounds of the invention occurs when R⁴ offormula (III), together with R⁶, forms an ether linkage; these compoundsmay be represented by the formula ##STR8##

Yet another class of compounds of the present invention, formed when Ais a group of formula (IV), may be represented by the formula ##STR9##

Representative compounds of the present invention include

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one("erythromycin A lactam enol ether");

[2R-(2R*,3S*,4S*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one("erythromycin B lactam enol ether");

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(methylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(ethylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(methyl(2-propenyl)amino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethyl(2-propenyl)ammonium)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabi-cyclo[10.2.1]pentadec-14-en-7-onebromide;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one13-O,14-O-carbonate;

[1R-(1R*,2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*,14S*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadecan-7-one;

[1R-(1R*,2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*,14S*)]-9-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15,16-dioxatricyclo[10.2.1.1¹,4]pentadecan-7-one;

[3R-(3R*,4S*,5S*,6R*,7R*,9S*,11R*,12R*,13R*,14R*)]-4-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-14-ethyl-7,12,13-trihydroxy-3,5,7,9,11,13-hexamethyl-6-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]azacyclotetradecane-2,10-dione("erythromycin A lactam");

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-.alpha.-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one("erythromycin C lactam enol ether");

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-.alpha.-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(ethylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3S*,4S*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-.alpha.-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one("erythromycin D lactam enol ether");

[2R-(2R*,3S*,4S*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-.alpha.-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(ethylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,6,8,10,12,14-heptamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,4,6-Trideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[2-O-acetyl-3,4,6-trideoxy-3-(dimethylamino)-.beta.-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,4,6-Trideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,4,6-Trideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,6,8,10,12,14-heptamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(n-butylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(n-propylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(i-propylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;and

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(i-butylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

as well as pharmaceutically acceptable salts thereof.

Preferred compounds of the present invention include

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one("erythromycin A lactam enol ether");

[2R-(2R*,3S*,4S*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one("erythromycin B lactam enol ether");

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(methylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(ethylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethyl(2-propenyl)ammonium)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabi-cyclo[10.2.1]pentadec-14-en-7-onebromide;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,6,8,10,12,14-heptamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,4,6-Trideoxy-3-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,4,6-Trideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,6,8,10,12,14-heptamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one;and

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(i-butylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

as well as pharmaceutically acceptable salts thereof.

The following terms are used as defined below throughout this disclosureand in the appended claims:

The term "carboxylate" as used herein refers to the anion of an organiccarboxylic acid such as acetic, succinic, citric, lactic, maleic,fumaric, palmitic, cholic, pamoic, music, D-glutamic, d-camphoric,glutaric, glycolic, phthalic, tartaric, formic, lauric, stearic,salicyclic, methanesulfonic, benzenesulfonic, sorbic, picric, benzoic,cinnamic and like acids.

The term "cyano-substituted loweralkyl" as used herein refers to aloweralkyl group as defined below which has one hydrogen atom replacedby a cyano substituent, as for example cyanomethyl or cyanoethyl.

The term "halogen" refers to chloro (Cl), bromo (Br), fluoro (F) andiodo (I).

The term "halo-substituted loweralkyl" refers to a loweralkyl group asdefined below which has one, two or three halogen substituents, as forexample fluoroethyl, difluoroethyl, chloromethyl, trifluoroethyl and thelike.

The term "hydroxy-substituted loweralkyl" refers to a loweralkyl groupas defined below which has one hydrogen atom replaced by a hydroxysubstituent, as for example hydroxymethyl or hydroxyethyl.

The term "loweralkanoyl" refers to a substituent of formula R¹⁰ C(O)--wherein R¹⁰ is hydrogen or a loweralkyl group as defined below.

The term "loweralkenyl" refers to straight or branched chain hydrocarbongroups containing from two to six carbon atoms and possessing at leastone carbon-carbon double bond. Examples of loweralkenyl groups includevinyl, allyl, 2- or 3-butenyl, 2-,3- or 4-pentenyl and isomeric formsthereof. The double bond(s) can be in either the cis or the transconfiguration.

The term "loweralkyl" refers to branched or straight chain alkyl groupscomprising one to six carbon atoms including, but not limited to,methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, neopentyland the like.

The term "loweralkynyl" refers to hydrocarbon groups containing from twoto six carbon atoms and possessing at least one carbon-carbon triplebond. Examples of loweralkynyl groups include ethynyl, propargyl andbutynyl.

The term "lowercycloalkyl" refers to cyclic hydrocarbons having three tosix ring carbon atoms.

The term "delayed gastric emptying" as used herein refers to a slowevacuation of gastric contents into the small intestine not caused bymechanical obstruction of the gastric outlet. Patients with severegastric motor dysfunction may be incapacitated from intractable nausea,vomiting and gastric stasis. This may lead to failure to thrive in ayoung patient or to significant weight loss and malnutrition in adults.(cf. "Medicine for the Practicing Physician Second Edition", ed. J.Willis Hurst, Butterworth Publishers, Boston, 1988, pages 1364-66.

The term "gastroparesis" refers to paralysis of the stomach.

The term "intestinal pseudoobstruction" refers to a conditioncharacterized by constipation, colicky pain and vomiting, but withoutevidence of organic obstruction apparent at laparotomy (abdominalsurgery).

The term "paralytic or adynamic ileus" refers to obstruction of theintestines resulting from inhibition of bowel motility.

The term "reflux esophagitis" refers to inflammation of the esophagus asa result of frequent or chronic backward or return flow of stomachcontents into the esophagus.

By "pharmaceutically acceptable salts" is meant those acid additionsalts of the compounds of formula (I) which are, within the scope ofsound medical judgement, suitable for use in contact with the tissues ofhumans and lower animals without undue toxicity, irritation, allergicresponse, and the like commensurate with a reasonable benefit/riskratio, and which are effective for their intended use.

Pharmaceutically acceptable salts are well known in the art. Forexample, S. M. Berge et al. describe pharmaceutically salts in detail inJ. Pharmaceutical Sciences, 1977, vol. 66, pages 1-19. Examples ofpharmaceutically acceptable, nontoxic acid addition salts are salts ofan amino group formed with inorganic acids such as hydrochloric acid,hydrobromic acid, phosphoric acid, sulfuric acid and perchloric acid orwith organic acids such as acetic acid, oxalic acid, maleic acid,tartaric acid, citric acid, succinic acid or malonic acid or by usingother methods used in the art such as ion exchange. Otherpharmaceutically acceptable salts include nitrate, bisulfate, borate,formate, butyrate, valerate, 3-phenylpropionate, camphorate, adipate,benzoate, oleate, palmitate, stearate, laurate, lactate, fumarate,ascorbate, aspartate, nicotinate, p-toluenesulfonate, camphorsulfonate,methanesulfonate, 2-hydroxyethanesulfonate, gluconate, glucoheptonate,lactobionate, glycerophosphate, pectinate, lauryl sulfate, alginate,cyclopentanepropionate, digluconate, dodecylsulfate, ethanesulfonate,hemisulfate, heptonate, hexanoate, 2-naphthalenesulfonate, pamoate,persulfate, pivalate, propionate, undecanoate salts and the like, andmay be prepared according to conventional methods. Representative alkalior alkaline earth metal salts include sodium, calcium, potassium,magnesium salts and the like. Pharmaceutically acceptable counterionsfor the quaternary ammonium salt compounds formed when R³ is presentinclude halide, hydroxide, carboxylate, sulfate, phosphate, nitrate,loweralkyl sulfonate and arysulfonate.

As used herein, the term "pharmaceutically acceptable carrier" means anon-toxic, inert solid, semi-solid or liquid filler, diluent,encapsulating material or formulation auxiliary of any type. Someexamples of materials which can serve as pharmaceutically acceptablecarriers are sugars such as lactose, glucose and sucrose; starches suchas corn starch and potato starch; cellulose and its derivatives such assodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate;powdered tragacanth; malt; gelatin; talc; excipients such as cocoabutter and suppository waxes; oils such as peanut oil, cottonseed oil,safflower oil, sesame oil, olive oil, corn oil and soybean oil; glycols,such as propylene glycol; polyols such as glycerin, sorbitol, mannitoland polyethylene glycol; esters such as ethyl oleate and ethyl laurate;agar; buffering agents such as magnesium hydroxide and aluminumhydroxide; alginic acid; pyrogen-free water; isotonic saline; Ringer'ssolution; ethyl alcohol, and phosphate buffer solutions, as well asother non-toxic compatible substances used in pharmaceuticalformulations. Wetting agents, emulsifiers and lubricants such as sodiumlauryl sulfate and magnesium stearate, as well as coloring agents,releasing agents, coating agents, sweetening, flavoring and perfumingagents, preservatives and antioxidants can also be present in thecomposition, according to the judgement of the formulator.

By a "therapeutically effective amount" of a compound of the inventionis meant a sufficient amount of the compound to treat a gastrointestinaldisorder, at a reasonable benefit/risk ratio applicable to any medicaltreatment. It will be understood, however, that the total daily usage ofthe compounds and compositions of the present invention will be decidedby the attending physician within the scope of sound medical judgement.The specific therapeutically effective dose level for any particularpatient will depend upon a variety of factors including the disorderbeing treated and the severity of the disorder; activity of the specificcompound employed; the specific composition employed; the age, bodyweight, general health, sex and diet of the patient; the time ofadministration, route of administration, and rate of excretion of thespecific compound employed; the duration of the treatment; drugs used incombination or coincidental with the specific compound employed; andlike factors well known in the medical arts.

The total daily dose of the compounds of this invention administered toa human or other mammal in single or in divided doses can be in amounts,for example, of from about 0.01 to about 25 mg/kg body weight or, moreusually, from about 0.1 to about 15 mg/kg body weight. Single dosecompositions may contain such amounts or submultiples thereof as make upthe daily dose. In general, treatment regimen according to the presentinvention comprise administration to a patient in need of such treatmentof from about 10 mg to about 1000 mg of the compound(s) of thisinvention per day in multiple doses or in a single dose.

Liquid dosage forms for oral administration may include pharmaceuticallyacceptable emulsions, microemulsions, solutions, suspensions, syrups andelixirs containing inert diluents commonly used in the art such aswater. Such compositions may also comprise adjuvants such as wettingagents; emulsifying or suspending agents and sweetening, flavoring orperfuming agents.

Injectable preparations, as for example sterile injectable aqueous oroleaginous suspensions, may be formulated according to the known artusing suitable dispersing or wetting agents and suspending agents. Thesterile injectable preparation may also be a sterile injectablesolution, suspension or emulsion in a nontoxic parenterally acceptablediluent or solvent, as for example in solution in 1,3-butanediol. Amongthe acceptable vehicles and solvents that may be employed are water,Ringer's solution, U.S.P. and isotonic sodium chloride solution. Inaddition, sterile, fixed oils are conventionally employed as a solventor suspending medium. For this purpose any bland fixed oil can beemployed including synthetic mono- or diglycerides. In addition, fattyacids such as oleic acid may be used in the preparation of injectables.

The injectable formulation can be sterilized, as for example byfiltration through a bacteria-retaining filter or by incorporatingsterilizing agents in the form of sterile solid compositions which canbe dissolved or dispersed in sterile water or other sterile injectablemedium just prior to use.

In order to prolong the effect of a drug, it is often desirable to slowthe absorption of a drug from subcutaneous or intramuscular injection.The most common way to accomplish this is to inject a suspension ofcrystalline or amorphous material with poor water solubility. The rateof absorption of the drug becomes dependent on the rate of dissolutionof the drug which is, in turn, dependent on the physical state of thedrug, as for example, its crystal size and crystalline form. Anotherapproach to delaying absorption of a drug is to administer the drug as asolution or suspension in oil. Injectable depot forms can also be madeby forming microcapsule matrices of drugs and biodegradable polymerssuch as polylactide-polyglycolide. Depending on the ratio of drug topolymer and the composition of the polymer, the rate of drug release canbe controlled. Examples of other biodegradable polymers includepoly-orthoesters and polyanhydrides. The depot injectables can also bemade by entrapping the drug in liposomes or microemulsions which arecompatible with body tissues.

Solid dosage forms for oral administration may include capsules,tablets, pills, powders, prills and granules. In such solid dosage formsthe active compound may be admixed with at least one inert diluent suchas sucrose, lactose or starch. Such dosage forms may also comprise, asis normal practice, additional substances other than inert diluents,e.g., tableting lubricants and other tableting aids such as magnesiumstearate and microcrystalline cellulose. In the case of capsules,tablets and pills, the dosage forms may also comprise buffering agents.Tablets and pills can additionally be prepared with enteric coatings andother release-controlling coatings.

Solid compositions of a similar type may also be employed as fillers insoft and hard-filled gelatin capsules using such exipients as lactose ormilk sugar as well as high molecular weight polyethylene glycols and thelike.

The active compounds can also be combined in micro-encapsulated formwith one or more excipients as noted above. The solid dosage forms oftablets, dragees, capsules, pills, and granules can be prepared withcoatings and shells such as enteric coatings and other coatings wellknown in the pharmaceutical formulating art. They may optionally containopacifying agents and can also be of a composition that they release theactive ingredient(s) only, or preferably, in a certain part of theintestinal tract, optionally in a delayed manner. Examples of embeddingcompositions which can be used include polymeric substances and waxes.

The compounds of the present invention may be synthesized by thereaction schemes I through VII presented below, in which A and R¹ --R⁹correspond to the groups defined with respect to formula (I). However,it should be noted that, prior to ring closure and formation of alactam, R⁶ in the following schemes is limited to hydrogen and --OH.Moreover, it will be observed that certain schemes, such as Scheme IA,are useful only where R⁶ is --OH.

Scheme I

Erythromycin A or C is treated with a suitable reagent for acetylatingthe 2'-hydroxyl group, such as acetic anhydride or acetyl chloride, inthe presence of a suitable base, such as triethylamine, pyridine orDMAP. The resulting 2'-O-acetyl compound is converted to aring-contracted compound of Formula 3 by treatment with an appropriatenonaqueous acid, such as glacial acetic acid followed by treatment witha suitable base, preferably in a polar solvent, as for example treatmentwith potassium carbonate in DMF or ammonium acetate in methanol.Alternatively, compounds of Formula 1 are converted directly into thecompounds of Formula 3 by the procedure described in Scheme 1A below.

The compound of Formula 3 is, in turn, converted to the epoxide ofFormula 4 by treatment withbis[a,a-bis(trifluoromethyl)benzene-methanolato]-diphenyl sulfur (Martinsulfurane). Alternately the hydroxy group on carbon number 13 isactivated by treatment with a suitable reagent, as for examplemethanesulfonyl chloride, and the activated ester is displaced to forman epoxide upon treatment with a suitable base, as for example sodium orpotassium hydroxide or sodium or potassium methoxide or t-butoxide,sodium or potassium carbonate. The epoxide ring of the compound ofFormula 4 is then opened to form an azido alcohol of Formula 5 bytreatment with a nucleophilic hydrozoic acid derivative, such as sodiumazide or potassium azide. The azido alcohol is, in turn, converted to anamino alcohol of Formula 10 by treatment with a suitable reducing agent,as for example by hydrogenation in the presence of a catalyst such asRaney nickel, palladium on carbon or platinum oxide, treatment with zincin acetic acid, or treatment with lithium aluminum hydride. The aminoalcohol is cyclized to form a lactam of Formula IA by treatment with asuitable base in a suitable solvent such as ammonium hydroxide inmethanol or 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in toluene.

Scheme IA

According to scheme IA, which is the preferred scheme for the synthesisof compounds of Formula 11, the compounds of Formula 1 are reacted in atwo-part procedure to convert them into compounds of Formula 3. Thecompound of Formula 1 is first treated with a strong organic acid, asfor example acetic acid, dichloroacetic acid, difluoroacetic acid,trichloroacetic acid or glycolic acid in a polar organic solvent such asmethanol, DMF or acetonitrile. The reaction intermediate is notisolated, but treated directly with a suitable base such as ammoniumacetate or potassium carbonate in a suitable organic solvent, such asmethanol, DMF or acetonitrile, to form the compound of Formula 3.Preferred reagents are dichloroacetic acid in acetonitrile, followed bypotassium carbonate in an aqueous mixture of acetonitrile and methanol.The compounds of Formula 3 are then converted to epoxides of Formula 4by the methods described above in reaction scheme I. These epoxides aresubsequently treated with an amine, as for example ammonia ormethylamine and preferably in a polar solvent, to afford the compoundsof Formula 11. More preferably, the compounds of Formula 4 are treatedwith a methanolic solution of the appropriate amine.

Scheme II

2'-O-Acetyl erythromycin (A, B, C or D) is treated with a suitablereagent for protecting the 4"-hydroxyl group, such as benzyloxycarbonylchloride, in the presence of a suitable base, such asdimethylaminopyridine. The reaction is carried out in an inert solventsuch as methylene chloride and preferably at a low temperature, morepreferably at -25° C., to afford a 2'-O-acetyl-4"-O-benzyloxycarbonylerythromycin derivative. This compound is optionally treated withmethanol to remove the acetyl group and is treated sequentially with asuitable nonaqueous acid, such as glacial acetic acid, and a suitablebase, such as potassium carbonate in DMF or ammonium acetate inmethanol, to afford a compound of Formula 6. A compound of Formula 6 isoptionally treated with a suitable reagent for reacetylating the2'-hydroxyl group and is treated with a suitable oxidizing agent such asN-chlorosuccinimide/dimethyl sulfide/triethylamine ortetrapropylammonium perruthenate/N-methylmorpholine N-oxide to give aketone of Formula 7. If the acetyl group is present it is removed withmethanol, and the protecting group on the 4"-hydroxyl group is removed(preferably by hydrogenolysis, if the protecting group is CBZ) to give acompound of Formula 8.

The ketone of Formula 8 is converted to an oxime of Formula 9 bytreatment with hydroxylamine in the presence of a suitable base such astriethylamine. The oxime of Formula 9 is reduced under suitableconditions, as for example 4 atmospheres of hydrogen over a catalystsuch as Raney nickel to afford a mixture of stereoisomers of the aminocompounds of Formula 10 (in which the amino bond is shown as a wavy lineto represent both steric orientations). One isomer of the amino compoundis cyclized to a lactam of Formula 11 by treatment with a suitable basein an appropriate solvent, as for example ammonium hydroxide in methanolor DBU in toluene.

Scheme III

According to reaction scheme III, an erythromycin lactam of Formula 11is treated with iodine and light in the presence of a suitable base,such as sodium acetate, to afford a N-demethyl derivative of Formula 12.A compound of Formula 12 is, in turn, treated with a suitable alkylatingagent such as allyl bromide to afford a compound of Formula 13.Alternatively, a compound of Formula 12 is treated with an appropriatealdehyde to give an imine which is reduced (preferably in situ) byhydrogenation in the presence of a suitable catalyst as for example,palladium on carbon, to afford a compound of Formula 13. The compoundsof Formula 13 are treated with iodine and light in the presence of asuitable base, for example sodium acetate, to afford the N-demethylderivative of Formula 14. A compound of Formula 14 is, in turn, treatedwith a suitable alkylating agent such as allyl bromide to afford acompound of Formula 15. Alternatively, a compound of Formula 14 istreated with an appropriate aldehyde, as for example acetaldehyde, togive an imine which is reduced (preferably in situ) by hydrogenation inthe presence of a suitable catalyst, as for example palladium on carbon,to afford a compound of Formula 15.

Other alkylating agents which may be used in preparing compounds ofFormula 13 and Formula 15 are loweralkyl halides such as ethyl bromide,halo-substituted loweralkyl halides, cyano-substituted loweralkylhalides, hydroxy-substituted loweralkyl halides, other loweralkenylhalides such as methylallyl chloride, loweralkynyl halides such aspropargyl bromide, lower cycloalkyl halides, lower cycloalkylmethylhalides such as lower cyclopropylmethyl and benzyl halides.

Scheme IV

According to reaction scheme IV, an erythromycin lactam derivative ofFormula 11 or 15 is treated with an a loweralkyl halide such as methyliodide or ethyl bromide, a loweralkenyl halide such as allyl bromide, aloweralkynyl halide such as propargyl bromide or a benzyl halide such asbenzyl bromide to afford a quaternary salt derivative of Formula 16.

Scheme V

According to reaction scheme V, an erythromycin A or C lactam of Formula11 or 15 (wherein R⁵ and R⁶ are both OH) is treated with a suitablecarbonic acid derivative such as ethylene carbonate, carbonyldiimidazole or thiocarbonyl diimidazole to afford a carbonate derivativeof Formula 17. Methods for preparing the loweralkanoyl and --S(O)₂ CH₃derivatives (compounds of formula (I) wherein R⁵ or R⁶ are loweralkanoyland --S(O)₂ CH₃) are well known in the art are, for example, aredescribed by S. Omura and Z. Itoh in European Application Number213,617, published Nov. 3, 1987. Alternatively, reaction of a suitablyprotected lactam of formula 11 or 15 with a base, for example, sodiumhydride, and an alkylating agent, such as methyl iodide, affords alkylderivatives wherein R5 or R6 may be a loweralkyl group.

Scheme VI

According to reaction scheme VI, an erythromycin lactam of Formula 11 isreduced by catalytic hydrogenation using a suitable catalyst such asplatinum oxide in the presence of a suitable acid such as difluoroaceticacid in a suitable solvent, preferably acetic acid, to afford thecompounds of Formula 18.

Scheme VII

According to reaction scheme VII, an erythromycin lactam of Formula 11(wherein R⁶ is OH) is treated with aqueous acid to afford a mixture ofcompounds which includes the compounds of Formulas 19 and 20. Thecompounds of Formulas 19 and 20 (wherein wavy lines indicate bothstereoisomers are formed) are also formed in vivo when compounds ofFormula 11 are exposed to the acidic conditions of the stomach.

Scheme VIII

According to Scheme VIII, the ring-contracted epoxide compound ofFormula 4 is treated with a suitable reagent for acetylating the2'-hydroxyl group, such as acetic anhydride or acetyl chloride, in thepresence of a suitable base, such as triethylamine, pyridine or DMAP.The compound of Formula 21 is converted to the 4"-deoxy compound bytreatment with 1,1'-thiocarbonyldiimidazole (Aldrich Chemical Co.,Milwaukee, Wis.) in the presence of a suitable base such astriethylamine, pyridine or DMAP. The compound of Formula 21 is in turntreated with a selective reducing agent, as for example tri-n-butyl tinhydride and AIBN (2,2'-azobis(2-methylpropionitrile), Alfa CatalogChemicals) in an inert atmosphere to give the 4"-deoxy compound ofFormula 23. This compound is then treated with an appropriate amine,such as ammonia or methylamine, and preferrably in a polar solvent, toafford the desired 4"-deoxy lactams (compounds 24 and 25). Thesecompounds may optionally be further modified by the reactions describedin the previous Schemes III-VII, substituting the compounds of Formula24 or 25 for compounds of Formula 11. ##STR10##

The foregoing may be better understood by reference to the followingexamples, which are provided for illustration only and are not intendedas a limitation of the invention.

EXAMPLE 1[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

Step 1: 2'-O-Acetylerythromycin A

Erythromycin A (50.0 g, 68.1 mmol) (commercially available from AbbottLaboratories) was dissolved in 600 mL of methylene chloride (CH₂ Cl₂) atambient temperature. Triethylamine (20 mL) and 10 mL (10.82 g, 106 mmol)of acetic anhydride were added to this solution. The reaction mixturewas heated to reflux and 100 mL of CH₂ Cl₂ was distilled from thereaction mixture to remove any traces of water. The reaction mixture washeated at reflux temperature for an additional five hours. After sixhours, when the reaction was complete, according to TLC analysis, thereaction mixture was cooled to ambient temperature and transferred to aseparatory funnel. The CH₂ Cl₂ solution was washed with 300 mL ofammonium hydroxide/sodium bicarbonate solution containing 2.9% ammoniaand 1.8% sodium bicarbonate, dried over anhydrous sodium sulfate andfiltered. The CH₂ Cl₂ was removed using a rotary evaporator with a waterbath temperature of 30°-40° C. The residue was crystallized from 200 mLof acetonitrile (CH₃ CN) by first dissolving it in hot CH₃ CN andallowing the solution to stand overnight at ambient temperature, thencooling it to -25° C. and maintaining this temperature for 24 hours. Theproduct was isolated as white crystals which were washed with cold (-25°C.) CH₃ CN and dried in a vacuum oven at 50° C. for approximately 64hours. The 2'-O-acetylerythromycin A was obtained in 83% yield (43.91g).

Step 2: 2'-O-Acetyl-8,9-didehydro-9-deoxo-6-deoxy-6,9-epoxyerythromycinA

2'-O-Acetylerythromycin A (20 g, 25.8 mmol) from Step 1 was dissolved in115 mL of glacial acetic acid. The resultant solution was stirred atambient temperature for 2 hours. The acetic acid was removed in vacuo.The complete removal of the acetic acid was accomplished by azeotropicdistillation with toluene. The residue was dissolved in 200 mL of ethylacetate and was washed with a mixture of 100 mL of 5% aqueous sodiumbicarbonate solution and 10 mL of concentrated aqueous ammoniumhydroxide solution. The aqueous layer was extracted with 3×100 mL ofethyl acetate. The combined ethyl acetate layers were washed with 200 mLof brine, dried over anhydrous sodium sulfate, filtered and concentratedin vacuo. The residue (19.67 g) was crystallized from ethyl acetate togive 13.54 g (69% yield) of the title compound: DCl-NH₃ MS M/Z: 758(M+H)⁺.

Step 3:[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-dihydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

2'-O-Acetyl-8,9-didehydro-9-deoxo-6-deoxy-6,9-epoxyerythromycin A (5.75g, 7.6 mmol) from Step 1 was dissolved in 35 mL of anhydrousN,N-dimethylformamide (DMF). Solid anhydrous potassium carbonate wasfinely powdered and added to the resultant solution. The suspension wasstirred at ambient temperature for 3 days. The reaction mixture wasdiluted with ice-water (100 mL) and was extracted with ethyl acetate(1×150 mL and 3×50 mL). The combined ethyl acetate layers were washedwith 100 mL of brine, dried over anhydrous sodium sulfate, filtered andconcentrated in vacuo. The residue (7.03 g) was chromatographed on 150 gof silica gel eluted with toluene:methanol (10:1). The residue wasdissolved in methanol and the solution was left overnight at ambienttemperature to cleave the acetyl group. The solution was concentrated invacuo to give 1.56 g (29% yield) of the title compound; IR (0.15% inCCl₄) 3600, 3550 and 1720 cm⁻¹.

Step 4:[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-dihydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(0.5 g, 0.7 mmol) from Step 3 was dissolved in 1 mL of dry methylenechloride and the resultant solution was added dropwise to a stirredsolution of 0.94 g (1.4 mmol) of stirredbis[a,a-bis(trifluoromethyl)benzene-methanolato]-diphenylsulfur (Martinsulfurane; commercially available from Aldrich Chemical Company) in 1 mLof dry methylene chloride. The reaction mixture was stirred for 45minutes and then poured into a separatory funnel containing 30 mL ofethyl acetate. Aqueous 5% sodium bicarbonate solution (30 mL) was addeduntil the pH of the solution was neutral. The ethyl acetate layer wasseparated and the aqueous mixture was extracted with 3×10 mL of ethylacetate. The combined ethyl acetate layers were washed with brine, driedover anhydrous sodium sulfate, filtered and concentrated in vacuo to ayellow oil. The residue was chromatographed on approximately 50 g ofsilica gel eluted sequentially with 2 L of toluene/acetone (5:1), 2, 125mL of toluene/methanol (10:1) and 1500 mL of toluene/methanol (5:2) togive 0.5 g of the title compound; DCl NH₃ MS M/Z: 698 (M+H)⁺ ; IR (0.15%in CCl₄) 3555 and 1725 cm⁻¹.

Step 5:[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-3-(2-Azido-1-hydroxy-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-79-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(14.19 g, 20.3 mmol), from Step 4, was dissolved in 350 mL of2-methoxyethanol. To this solution, with stirring, was added a solutionof 10.6 g (0.163 mmol) of sodium azide and 0.853 g (0.16 mmol) ofammonium chloride in 141 mL of water. The reaction mixture was heated atreflux temperature for 5 days. The reaction mixture was transferred to aseparatory funnel and 200 mL of 5% aqueous sodium bicarbonate was added.The mixture was extracted with 200 mL of methylene chloride followed by2×100 mL of methylene chloride. The combined organic layers were washedwith brine, dried over anhydrous sodium sulfate, filtered andconcentrated in vacuo to a yellow oil. The oil was chromatographed onapproximately 500 g of silica gel eluted withchloroform/methanol/ammonia (10:1:0.0125) to give 8.5 g (57% yield) ofthe title compound as a yellow glass; DCl NH₃ MS M/Z: 741 (M+H)⁺ ; IR(0.15% in CCl₄) 3590, 3548, 3470, 2110 and 1735 cm⁻¹.

Step 6:[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-3-(2-Amino-1-hydroxy-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-3-(2-Azido-1-hydroxy-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(1 g, 1.35 mmol) from Step 5, 4.5 g of Raney nickel and 100 mL ofmethanol were combined under 4 atmospheres of hydrogen and the mixturewas shaken at ambient temperature for 24 hours. The catalyst was removedby filtration and the filtrate concentrated under reduced pressure to alight-green glass. The glass (1.08 g) was dissolved in 100 mL ofmethylene chloride and washed with 100 mL of 5% aqueous sodiumbicarbonate. The aqueous layer was extracted with 3×50 mL of methylenechloride. The combined organic layers were washed with brine, dried overanhydrous sodium sulfate, filtered and concentrated in vacuo to 880 mg(91% yield) of the title compound; DCI NH₃ MS M/Z: 715 (M+H)⁺ ; IR(0.15% in CCl₄) 3595, 3548, 3470, and 1725 cm⁻¹. Analysis calculated forC₃₇ H₆₆ N₂ O₁₁ : C, 62.16; H, 9.31; N, 3.92. Found: C, 62.19; H, 9.21;N, 3.52.

Step 7:[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(di-methylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-3-(2-Amino-1-hydroxy-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(0.81 g, 1.1 mmol) was dissolved in 88 mL of methanol. Ammoniumhydroxide (8.5 mL) was added and the reaction mixture was stirred atambient temperature for 24 hours. The solvent was removed in vacuo.Methylene chloride was added to and evaporated from the residue twice toremove residual water affording 770 mg (95% yield) of the titlecompound: DCl NH₃ MS M/Z: 715 (M+H)⁺ ; IR (0.15% in CCl₄) 3560, 3442,3358, 1703 and 1660 cm⁻¹.

EXAMPLE 1 A Alternate preparation of [2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

Step 1:[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-dihydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8,2,1]tridec-12-en-5-one(the product of Step 3 of Example 1)

Erythromycin A (100 g, 136.25 mmol) was dissolved in 1 L of methanol and62.5 mL (1090 mmol, 8 equivalents) of glacial acetic acid was added. Thereaction mixture was heated to reflux and refluxed for 4.25 hours. Thereaction mixture was then cooled in an ice bath and to the cooledmixture was added, dropwise over a 15 minute period, 73.5 mL (1090 mmol,8 equivalents) of concentrated ammonium hydroxide. The reaction mixturewas then brought to reflux and refluxed for 24 hours. After keeping thereaction mixture at 25° C. overnight, it was concentrated to a solidmass under reduced pressure using a water bath at 55° C. The residue wastaken up in a mixture of 500 mL of ethyl acetate, 400 mL of water and100 mL of concentrated ammonium hydroxide. After stirring forapproximately 20 min, the ethyl acetate layer was separated and theaqueous layer was extracted with 250 mL of ethyl acetate. The combinedethyl acetate solution was washed with 2×350 mL of brine and 2×350 mL ofwater, dried over anhydrous sodium sulfate, filtered and concentrated todryness. The residue was dried at 25° C. (1 mm Hg) for 18 hours toafford 93.1 g of the crude product. The crude product was dissolved in300 mL of acetonitrile and allowed to crystallize (4 hours at ambienttemperature and approximately 65 hours at -25° C.). The crystals weredried at 65° C. (over P₂ O₅) in a vacuum oven to give 54.2 g of thetitle compound, m.p. 125°-130° C.

Step 2:[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8,2,1]tridec-12-en-5-one

[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-dihydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(0.5 g, 0.7 mmol) from Step 1 was dissolved in 1 mL of dry methylenechloride and the resultant solution was added dropwise to a stirredsolution of 0.94 (1.4 mmol) ofbis[a,a-bis(trifluoromethyl)benzene-methanolato]-diphenylsulfur (Martinsulfurane; commercially available from Aldrich Chemical Company) in 1 mLof methylene chloride. The reaction mixture was stirred for 45 minutesand then poured into a separatory funnel containing 30 mL of ethylacetate. Aqueous 5% sodium bicarbonate solution (30 mL) was added untilthe pH of the solution was neutral. The ethyl acetate layer wasseparated and the aqueous mixture was extracted with 3×10 mL of ethylacetate. The combined ethyl acetate layers were washed with brine, driedover anhydrous sodium sulfate, filtered and concentrated in vacuo to ayellow oil. The residue was chromatographed on approximately 50 g ofsilica gel eluted sequentially with 2 L of toluene/acetone (5:1), 2,125mL of toluene/methanol (10:1) and 1500 mL of toluene/methanol (5:2) togive 0.5 g of the title compound; DCl NH₃ MS M/Z: 698 (M+H)⁺ ; IR (0.15%in CCl₄) 3555 and 1725 cm⁻¹.

Step 3:[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(2.00 g, 2.87 mmol), from Step 2, was dissolved in 16 mL of methanol, ina heavy-walled glass reaction tube. To the resultant solution was added4.0 mL of concentrated ammonium hydroxide (59.2 mmol ammonia, 20.6equivalents). The tube was sealed with a Teflon® "O" ring-type-screwplug. The reaction mixture was then heated to 90°-92° C. in an oil bath.The progress of the reacton was followed by HPLC using a YMC reversephase R-ODS-7 HPLC column eluted at 1.00 mL/minute with 60% aqueousmethanol containing 10 g/L of ammonium acetate trihydrate, 25 mL/Lglacial acetic acid and 50 mL/L of tetrahydrofuran. After 6 days, thereaction mixture was cooled to ambient temperature and then diluted with250 mL of 8% aqueous sodium bicarbonate solution. The pH of the solutionwas brought to 10 by the addition of 10 mL of concentrated ammoniumhydroxide and the basic solution was extracted with 3×50 mL portions ofchloroform. The combined chloroform extracts were washed with 50 mL of a1:1 solution of 8% aqueous sodium bicarbonate and brine, dried overanhydrous sodium sulfate, filtered and concentrated in vacuo in a waterbath at 45° C. The residue was dried at 25° C. under vacuum for 3 hoursto give 2.277 g of crude product. A column of silica gel (100 g), whichhad been washed with 1 L of 40% methanol in acetonitrile containing 2%concentrated ammonium hydroxide and 1 L of 0.1% concentrated ammoniumhydroxide in acetonitrile, was equilibrated with 0.5 L of the eluent,10% acetonitrile in chloroform containing 3.0% methanol and 0.3%concentrated ammonium hydroxide. The crude product was thenchromatographed, eluting at 2.5 mL/minute. The fractions containing thedesired product were combined and concentrated in vacuo in a water bathat 45° C. The residue was dissolved in 50 mL of methanol and theresultant solution was filtered and concentrated in vacuo to give, afterdrying in vacuo at 25° C. for 3 days, 1.752 g (85.4% yield) of the titlecompound. A sample was crystallized from acetonitrile at -25° C. to giveneedle-like crystals, m.p. 152°-156° C. after drying at 1 Torr/100° C.;[α]_(D) ²³ =-39.2° (c 1.00; MeOH)

EXAMPLE 2 [2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

Step 1: 2'-O-Acetyl-4"-O-benzyloxycarbonylerythromycin A

2'-O-Acetylerythromycin A (30 g, 38.6 mmol), the product of Step 1 ofExample 1, was dissolved in 150 mL of methylene chloride.Dimethylaminopyridine (18.3 g, 149.8 mmol) was added and the solutionwas cooled to -40° C. in an acetonitrile/dry ice bath. Benzyloxycarbonylchloride (16.8 mL, 110 mmol) was added and the solution was stirred at-40° C. until a gel formed. After keeping the reaction mixture at -25°C. for 3 days, the mixture was poured into a separatory funnel and waswashed with phosphate buffer (pH 5.0). The organic layer was washed with5% aqueous sodium bicarbonate. The aqueous sodium bicarbonate layer wasextracted with methylene chloride. The combined organic layers werewashed with brine, dried over anhydrous sodium sulfate, filtered andconcentrated to an off-white glass. The glass was recrystallized fromacetonitrile to give 21.39 g (61% yield) of the title compound; DCl NH₃MS M/Z: 910.

Step 2:2'-O-Acetyl-4"-O-benzyloxycarbonyl-8,9-didehydro-9-deoxo-6-deoxy-6,9-epoxyerythromycinA

2'-O-Acetyl-4"-O-benzyloxycarbonylerythromycin A (21.29 g, 23.37 mmol),from Step 1, was dissolved in 115 mL of glacial acetic acid and theresultant solution was stirred at ambient temperature for 2 hours. Theacetic acid was azeotropically removed in vacuo using toluene. Theresidue was dissolved in 500 mL of ethyl acetate and the ethyl acetatesolution was washed with a mixture of 300 mL of 5% aqueous sodiumbicarbonate solution and 10 mL of ammonium hydroxide. The aqueous layerwas extracted with 100 mL of ethyl acetate. The combined organic layerswere washed with brine, dried over anhydrous sodium sulfate, filteredand concentrated in vacuo to give 19.39 g (93% yield) of the titlecompound as a white glass; DCl NH₃ MS M/Z: 892.

Step 3:[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-Acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-dihydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

Following the procedures described in Step 3 of Example 1, and purifyingthe product by chromatography on silica gel eluted with toluene/acetone(5:1) followed by toluene/acetone (10:3), 5.3 g (5.95 mmol) of theproduct of Step 2 above was treated with potassium carbonate in DMF togive 1.46 g (28% yield) of the title compound; DCl NH₃ MS M/Z: 892; IR(5% in CDCl₃) 3595, 3560 and 1740 cm⁻¹.

Step 4:[2R-[2R*,3R*(1S*),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-Acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1-hydroxy-1-methyl-2-oxobutyl)-2,6,8,10,12-pentamethyl-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

N-chlorosuccinimide (0.57 g, 4.27 mmol) was dissolved in 5.05 mL oftoluene and the resultant solution was cooled to -10° C. Dimethylsulfide (0.41 mL, 5.58 mmol) was added and the solution was stirred at-10° C. for 20 minutes. A solution of[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-acetyl-3,4,6-trideoxy-3'-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-dihydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(0.5 g, 0.56 mmol), from Step 3, in 1.28 mL of toluene was added and thereaction mixture was stirred at -40° C. for 3.5 hours. The reaction wasthen quenched by the addition of triethylamine and the reaction mixturewas transferred to a separatory funnel and a 5% aqueous sodiumbicarbonate solution was added. The aqueous layer was extracted with4×50 mL of toluene and once with 50 mL of methylene chloride. Thecombined organic layers were washed with brine, dried over anhydroussodium sulfate, filtered and concentrated in vacuo to give 0.455 g (91%yield) of the title compound; DCl NH₃ MS M/Z: 890; IR (5% in CDCl₃) 3540and 1740 cm⁻¹.

Step 5:[2R-[2R*,3R*(1S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1-hydroxy-1-methyl-2-oxobutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1S*),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-Acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1-hydroxy-1-methyl-2-oxobutyl)-2,6,8,10,12-pentamethyl-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(3.57 g, 4.02 mmol), from Step 4, was dissolved in 200 mL of methanol.To this solution was added 3.57 g of 10% palladium on carbon. Thereaction mixture was shaken at ambient temperature under 4 atmospheresof hydrogen for 24 hours. The catalyst was removed by filtration and thefiltrate was concentrated in vacuo. The residue (2.5 g) was dissolved in200 mL of methylene chloride. The methylene chloride solution was washedwith 100 mL of 5% aqueous sodium bicarbonate. The aqueous wash wasextracted with 3×50 mL of methylene chloride. The combined organiclayers were washed with brine, dried over anhydrous sodium sulfate,filtered and concentrated in vacuo to give 2.01 g (70% yield) of thetitle compound; FAB MS M/Z: 714 (M+H)⁺.

Step 6:[2R-[2R*,3R*(1R*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1-hydroxy-1-methyl-2-oximidobutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1-hydroxy-1-methyl-2-oxo-butyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(0.5 g, 0.7 mmol), from Step 5, was dissolved in 10 mL of ethyl alcohol.To this solution was added 0.39 g (6.05 mmol) of hydroxylaminehydrochloride and 0.6 mL (4.23 mmol) of triethylamine. The reactionmixture was heated at reflux temperature for 84 hours. The reactionmixture was allowed to cool to ambient temperature and then it waspoured into a separatory funnel along with 200 mL of methylene chlorideand washed with 100 mL of 5% aqueous sodium bicarbonate. The aqueouslayer was extracted with 2×50 mL of methylene chloride, washed withbrine, dried over anhydrous sodium sulfate, filtered and concentrated invacuo. The residue (200 mg out of total of 410 mg) was chromatographedon 50 g of silica gel eluted with chloroform/methanol/ammonia(10:1:0.015) to give 77.8 mg of the title compound; FAB MS M/Z: 729(M+H)⁺ ; IR (0.15% in CCl₄) 3595 and 1733 cm⁻¹.

Step 7:[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

A mixture of 100 mg (0.137 mmol) of [2R-[2R*,3R*(1R*), 6R*, 7S*, 8S*,9R*,10R*]]-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1-hydroxy-1-methyl-2-oximidobutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one,0.56 g of Raney nickel and 10 mL of ammonia in 90 mL of methanol wasshaken at ambient temperature under 4 atmospheres of hydrogen for 24hours. The catalyst was removed by filtration and the filtrate wasconcentrated in vacuo to a foam. The foam was dissolved in 50 mL ofmethylene chloride and washed with 30 mL of 5% aqueous sodiumbicarbonate. The aqueous layer was extracted with 3×25 mL of methylenechloride. The combined organic layers were washed with brine, dried overanhydrous sodium sulfate, filtered and concentrated in vacuo to give99.8 mg of the title compound; LSIMS/NBA, DMF M/Z: 715 (M+H)⁺ ; IR(0.15% in CCl₄) 3560, 3440, 3355, 1703 and 1660 cm⁻¹.

EXAMPLE 3[2R-(2R*,3S*,4S*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

Step 1: 2'-O-Acetylerythromycin B

Following the procedures described in Step 1 of Example 1, replacingerythromycin A with erythromycin B, the title compound was prepared.

Step 2: 2'-O-Acetyl-4"-O-benzyloxycarbonylerythromycin B

A mixture of 30.60 g (40.264 mmol) of 2'-O-acetylerythromycin B and15.00 g (122.78 mmol) of dimethylaminopyridine (DMAP) was dissolved in75 mL of methylene chloride. The resultant solution was cooled to -25°C. in a dry ice/CCl₄ bath. Benzylchloroformate (11.5 mL, 56.41 mmol) wasadded and the mixture was stored at -25° C. overnight. TLC analysisindicated incomplete reaction, therefore, DMAP (7.5 g) andbenzylchloroformate (6 mL) were added and the mixture stirred at -25° C.for 6 hours. The reaction mixture was then diluted with 400 mL of ethylacetate and was washed sequentially with 2×100 mL of 4% aqueous sodiumbicarbonate, 100 mL of brine, 3×100 mL of 10% aqueous potassiumdihydrogen phosphate/brine (4:1), 100 mL of brine and 100 mL of 4%aqueous sodium bicarbonate solution. The ethyl acetate solution wasdried over anhydrous sodium sulfate, filtered and concentrated in vacuoto a semi-solid glass. The residue (45.14 g) was triturated with 300 mLof heptane to give 33.44 g (93% yield) of the title compound.

Step 3:[2R-[2R*,3S*(1S*,2R*),6R*,7S*,8S*,9R*,10R*]]-7-[(4-O-Benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(2-hydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

2'-O-Acetyl-4"-O-benzyloxycarbonylerythromycin B (10.11 g, 11.307 mmol)was dissolved in 250 mL of methanol and the solution was allowed tostand at 25° C. for 3 days. Glacial acetic acid (5.43 mL (94.92 mmol)was added and the resultant mixture was heated at reflux temperature for48 hours. The reaction was then cooled to ambient temperature and 6.41mL (94.92 mmol) of concentrated ammonium hydroxide was added. Thereaction mixture was heated at reflux temperature for 9 days. Thereaction mixture was concentrated to 25 mL and then diluted with 300 mLof 4% aqueous sodium bicarbonate. The aqueous mixture was extracted with1×100 mL of chloroform followed by 2×50 mL of chloroform. The combinedorganic extracts were washed with 100 mL of 4% aqueous sodiumbicarbonate, dried over anhydrous sodium sulfate, filtered andconcentrated in vacuo. Acetonitrile was added to the residue toazeptropically remove residual chloroform and water and evaporated underreduced pressure to give 8.91 g of the title compound which was taken onto the next step without purification.

Step 4:[2R-[2R*,3S*(1S*,2R*),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-Acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(2-hydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3S*(1S*,2R*),6R*,7S*,8S*,9R*,10R*]]-7-[(4-O-Benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(2-hydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(8.84 g, 10.599 mmol), from Step 3, was dissolved in 175 mL of methylenechloride. Acetic anhydride (3.5 mL) and triethylamine (9 mL) were addedand the reaction mixture was allowed to stand at ambient temperature for2.5 days. The reaction mixture was concentrated in vacuo and the residuewas dissolved in 200 mL of ethyl acetate. The ethyl acetate solution waswashed with 4×50 mL of 4% aqueous sodium bicarbonate solution. Solidsodium chloride (20 mL) was added to each of the second, third andfourth washes to improve the phase separation. The ethyl acetatesolution was dried over sodium sulfate, filtered and concentrated invacuo to give 9.12 g of the title compound as a white glass; IR (0.15%in CCl₄): 3530, 1748 and 1718 cm⁻¹.

Step 5:[2R-[2R*,3R*(1R),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-Acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2-oxobutyl)-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

A mixture of 5.197 g (5.932 mmol) of[2R-[2R*,3S*(1S*,2R*),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(2-hydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-onefrom Step 4, 4.20 g (35.85 mmol) of N-methylmorpholine N-oxide and 2.5 gof 4 Å molecular sieves in 26 mL of methylene chloride was stirred at20° C. for 1 hour. The reaction mixture was then cooled to -15° C. in anice/acetone bath and after 15 minutes, 30.9 mg (0.879 mmol) oftetrapropyl-ammonium perruthenate was added. After stirring for severalminutes at -15° C. the reaction was allowed to stand at -15° C. for 20hours. The reaction mixture was then filtered into a stirred mixture of11 g of sodium bisulfite in 100 mL of water, using 200 mL of ethylacetate to wash the filter cake. The filtrate was diluted with 100 mL ofwater and after vigorously stirring for 1 hour was filtered. The aqueouslayer was separated and discarded. The organic layer was washed with2×100 mL of a 50/50 mixture of brine and 4% aqueous sodium bicarbonate.The ethyl acetate solution was dried over anhydrous sodium sulfate,filtered and concentrated in vacuo to give 4.65 g (90% yield) of thetitle compound as a white glass.

Step 6:[2R-[2R*,3R*(1R*),6R*,7S*,8S*,9R*,10R*]]-7-[(4-O-Benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2-oxobutyl)-9-[[3,4,6-trideoxy-3-(dimethylamino)-.beta.-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1R*),6R*,7S*,8S*,9R*,10R*]]-9-[[2-O-Acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-7-[(4-O-benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2oxobutyl)-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(4.65 g, 5.3 mmol), from Step 5, was dissolved in 100 mL of methanol andkept at 25° C. for 4 days. A small amount of precipitate was removed byfiltration and the solvent was removed in vacuo. The dried residue (4.39g) was chromatographed on 200 g of silica gel which had beenpreconditioned and was eluted with ethyl acetate/heptane/ammoniumhydroxide (69.8:30:0.2) to give 1.57 g (35% yield) of the title compoundas a white foam.

Step 7:[2R-[2R*,3R*(1R*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2-oxobutyl)-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1R*),6R*,7S*,8S*,9R*,10R*]]-7-[(4-O-Benzyloxycarbonyl-2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2-oxobutyl)-9-[[3,4,6-trideoxy-3-(dimethylamino)-.beta.-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one[8.2.1]tridec-12-en-5-one (1.52 g, 1.83 mmol) was dissolved in 100 mL ofmethanol. To the resultant solution was added 75 mg of 10% palladium oncarbon. The reaction mixture was shaken at ambient temperature under 4atmospheres of hydrogen for 1 hour. TLC analysis on silica gel plateseluted with chloroform/methanol/concentrated ammonium hydroxide(9.5:0.5:0.2) indicated that the reaction was complete. The catalyst wasremoved by filtration and the filter cake was washed with 100 mL ofmethanol. The filtrate was concentrated under reduced pressure to give1.267 g (99% yield) of the title compound.

Step 8:[2R-[2R*,3S*(1S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2-oximidobutyl)-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3R*(1R*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2-oxobutyl)-9-[[3,4,6-trideoxy-3-(dimethylamino))-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(1.211 g, 1.735 mmol), from Step 7, was dissolved in 82 mL of absoluteethyl alcohol. To this solution was added 601 mg (8.65 mmol) ofhydroxylamine hydrochloride, followed by 725 μL (5.18 mmol) oftriethylamine. The reaction mixture was heated at reflux temperature andmonitored by analytical HPLC on a YMC reverse phase AQ-303 column elutedat 1 mL/min with water/acetonitrile/methanol (5:4.5:0.5) containing 6.5g/L of ammonium acetate. After 18 hours, the reaction mixture wasconcentrated to a few mLs. Ethyl acetate (150 mL) and 33 mL of 8%aqueous sodium bicarbonate solution were added. The organic layer waswashed with 2×33 mL of 8% aqueous sodium bicarbonate, dried overanhydrous sodium sulfate, filtered and concentrated in vacuo. Theresidue was carried on to the next step without purification.

Step 9: Diastereomeric mixture of[2R-[2R*,3S*(1S*,2R*),6R*,7S*,8S*,9R*,10R*]]-3-(2-amino-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-oneand

[2R-[2R*,3S*(1S*,2S*),6R*,7S*,8S*,9R*,10R*]]-3-(2-amino-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

[2R-[2R*,3S*(1S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-3-(1-methyl-2-oximidobutyl)-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(997 mg), from Step 8, was dissolved in 10% ammonium hydroxide in 100 mLof methanol. To this solution was added 2.5 g of Raney nickel and thereaction mixture was shaken at ambient temperature under 4 atmosphere ofhydrogen for 18 hours. The catalyst was removed by filtration and thefiltrate was concentrated under reduced pressure. The dry residue (895mg) was dissolved in 120 mL of ethyl acetate and the ethyl acetatesolution was washed with 3×33 mL of 8% aqueous sodium bicarbonatesolution and 30 mL of brine, dried over anhydrous sodium sulfate,filtered and concentrated in vacuo to give 799 mg of the title mixtureas a white glass. The product was carried on to the next step withoutpurification.

Step 10:[2R-(2R*,3S*,4S*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

The diastereomeric mixture of[2R-[2R*,3S*(1S*,2R*),6R*,7S*,8S*,9R*,10R*]]-3-(2-amino-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-oneand[2R-[2R*,3S*(1S*,2S*),6R*,7S*,8S*,9R*,10R*]]-3-(2-amino-1-methylbutyl)-7-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(345.1 mg) was dissolved in 9.0 mL of methanol. To this solution wasadded 1.0 mL of concentrated ammonium hydroxide and the resultantsolution was heated at 45° C. in a screw capped vial for 9 days. Thesolution was concentrated in vacuo to give 338.6 of a glass. The glass(300 mg) was dissolved in 2.0 mL of methanol and purified by preparativeHPLC chromatography. The HPLC column, a D-ODS-7 (20×250 cm) C8 reversephase column was eluted at 14 mL/min. The eluent was prepared bydilution of 36 g of ammonium acetate with 2.1 L of water and 1 L ofacetonitrile. The methanol solution was filtered through a 45μ nylonfilter and injected onto the column in 5 batches (4×400 μL and 1×200μL). The first peak to elute from the column (fraction A; RT=18.6 min)was collected in a flask containing 150 mL of 1N aqueous ammoniumhydroxide. The second peak to elute from the column (fraction B) wascollected at 22.8 min. Each fraction was separately concentrated invacuo at 45° C. to remove acetonitrile. 10% Aqueous sodium carbonatesolution (25 mL) was added to the resulting aqueous mixture which wasextracted with 5×20 mL of chloroform. The combined chloroform extractswere washed with a mixture of 15 mL of brine and 2 mL of concentratedammonium hydroxide, dried over anhydrous sodium sulfate, filtered andconcentrated in vacuo. Acetonitrile was added to the residue toazeotropically remove residual chloroform and water and evaporated underreduced pressure to give 65.4 mg (19% yield) of Fraction A (the titlecompound) and 105 mg (31% yield) of Fraction B (the 2S*-2-aminodiastereomer). Fraction A: FAB MS M/Z: 699 (M+H)⁺ ; IR (0.15% in CCl₄)3565, 3480, 1650 cm⁻¹. Fraction B: FAB MS M/Z: 699 (M+H)⁺ ; IR (0.15% inCCl₄) 3558, 3470, 1720 cm⁻¹.

EXAMPLE 4 [2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(methylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(2 g, 2.8 mmol), the product of Example 1, was dissolved in 40 mL ofmethanol. To this solution at ambient temperature was added 1.9 g (14mmol) of sodium acetate, followed by 390 mg (1.54 mmol) of iodine, andthe resultant solution was exposed to light for 45 minutes. The iodinecolor was no longer visible. A second portion of iodine (390 mg, 1.54mmol) was added and the solution again exposed to light for 1.5 hours.The reaction mixture was then poured into a separatory funnel containing50 mL of methylene chloride and washed with a mixture of approximately21 mL of brine and 50 mL of 5% aqueous sodium bicarbonate solutioncontaining 100 mg of sodium thiosulfate. The aqueous layers wereextracted with 5×25 mL of methylene chloride. The combined organiclayers were washed with brine, dried over anhydrous sodium sulfate,filtered and concentrated in vacuo. The residue (1.82 g) waschromatographed on 150 g of silica gel eluted withchloroform/methanol/ammonia (100:3:0.3) to give 865 mg (44% yield) ofthe title compound; FAB MS M/Z: 701 (M+H)⁺ ; IR (0.15% in CCl₄) 3560,3438, 3353 and 1660 cm⁻¹.

In another run, the solvent used for workup was ethyl acetate instead ofmethylene chloride, and the product was crystallized from acetonitrile,instead of being purified by chromatography. mp 170°-175° C. [α]_(D)=-29.0° (c=1.00, MeOH, 28° C.). IR (CCl₄) 963, 1665, 1700 cm⁻¹. AnalCalc. for C₃₆ H₆₄ N₂ O₁₁ : C, 61.69; H, 9.20; N, 4.00; Found: C, 61.39;H, 9.02; N, 3.95.

EXAMPLE 5[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(ethylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(methylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(53 mg, 0.076 mmol), the product of Example 4, was dissolved in 3 mL ofmethanol. To this solution was added 25 mg of 10% palladium on carbonand 50 μL (0.82 mmol) of acetaldehyde. The reaction mixture was shakenat ambient temperature under 4 atmospheres of hydrogen for 18 hours. Thecatalyst was removed by filtration and the filtrate was concentrated invacuo. The residue was washed with 50 mL of 5% aqueous sodiumbicarbonate and the aqueous mixture was extracted with 3×7 mL ofmethylene chloride. The combined organic extracts were washed with brineand concentrated in vacuo. The residue (43.3 mg) was combined withadditional material from an identical reaction (total=200 mg) andchromatographed on a 1×40 cm silica gel column eluted withtoluene/methanol (20:1) to give 98.6 mg of solid. The solid wasdissolved in 4 mL of acetonitrile and filtered. The filtrate wasconcentrated in vacuo to give 62.8 mg of the title compound; FAB MS M/Z:729 (M+H)⁺ ; IR (0.15% in CCl₄) 3560, 3440, 3355 and 1660 cm⁻¹.

EXAMPLE 6[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(methyl(2-propenyl)amino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(methylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(60.9 mg, 0.087 mmol), the product of Example 4, was dissolved in 1.5 mLof acetonitrile. To this solution was added 25 μL (0.289 mmol) of coldallyl bromide and the reaction mixture was stirred at ambienttemperature for approximately 8 hours. The reaction mixture was dilutedwith 50 mL of 5% aqueous sodium bicarbonate solution and was extractedwith 3×15 mL of methylene chloride. The combined organic layers werewashed with brine, dried over anhydrous sodium sulfate, filtered andconcentrated in vacuo to a glassy solid. The glass (54.8 mg) waspurified by chromatography on silica gel eluted with toluene/methanol(20:1) to give 19.6 mg (31 % yield) of the title compound; FAB MS M/Z:741 (M+H)⁺.

EXAMPLE 7[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethyl(2-propenyl)ammonium)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabi-cyclo[10.2.1]pentadec-14-en-7-onebromide

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(200 mg, 0.28 mmol), the product of Example 1, was dissolved in 3 mL ofacetonitrile. To this solution was added 80 μL (0.924 mmol) of allylbromide and the reaction mixture was stirred at ambient temperature for2 hours. The reaction mixture was concentrated in vacuo. The residue wastriturated with ethyl acetate. The solid phase was dried in vacuo togive 160 mg (68% yield) of the title compound; FAB MS M/Z: 755 (M⁺ -Br);IR (KBr) 1703, 1650 cm⁻¹.

EXAMPLE 8 [2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7one13-O,14-O-carbonate

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(177 mg, 0.248 mmol), the product of Example 1, was dissolved in 2 mL oftoluene/THF (1:1). To this solution was added 0.37 g (2.68 mmol) ofpotassium carbonate, followed by 0.78 g (8.86 mmol) of ethylenecarbonate (commercially available from Aldrich Chemical Company). Thereaction mixture was heated at reflux temperature for 3 hours, cooled toambient temperature, diluted with 50 mL of 5% aqueous sodium bicarbonateand extracted with 3×25 mL of toluene. The organic phase was washed with50 mL of brine and concentrated in vacuo to an oil which solidified uponstanding at ambient temperature. The residue was chromatographed onsilica gel eluted with chloroform/acetonitrile/methanol/ammonia(10:2.5:0.25:0.03) to give 66.7 mg (19% yield) of the title compound;DCl NH₃ MS M/Z: 741 (M+H)⁺ ; IR (0.15% in CCl₄) 3560, 3440, 3358, 1805and 1678 cm⁻¹.

EXAMPLE 9 [1R-(1R*,2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*,14S*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadecan-7-one

[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(210.7 mg, 0.295 mmol), the product of example 1, was dissolved in 20 mLof glacial acetic acid. To the resultant solution was added 40 μL (2.157equivalents) of difluoroacetic acid (DFA) and 210 mg of platinum oxide.The reaction mixture was shaken at ambient temperature under 4atmospheres of hydrogen for 4 hours. Ammonium acetate (160 mg) was addedand the resultant mixture was shaken for 10 minutes. The catalyst wasremoved by filtration and the filtrate was concentrated under reducedpressure. The residue was diluted with 50 mL of chloroform. A mixture of50 mL of brine and 10 mL of concentrated ammonium hydroxide was added.The chloroform layer was separated and the aqueous layer was extractedwith 30 mL of chloroform. The combined chloroform layers were washedwith a mixture 40 mL of brine and 5 mL of concentrated ammoniumhydroxide. The chloroform solution was dried over anhydrous sodiumsulfate, filtered and concentrated. The residue was evaporated fromacetonitrile to remove all of the chloroform and dried under vacuum togive 230.4 mg of a white glass. The title compound was separated fromthe other components of the crude product by preparative HPLC on areverse phase YMC D-ODS-7 column (20×250 mm) eluted at 10 mL/min with40% methanol in water containing 10 g/L of triethylamine hydrochloride,0.1 mL/L of glacial acetic acid and 30 mL/L of ethylene glycol. Thecrude product (the white glass) was dissolved in 2.0 mL of methanol andthe solution was filtered through a 0.4μ nylon filter. The methanolsolution was injected onto the HPLC column in 6 portions totalling 1.755mL. The peal collected at 14.7 min was combined from each run andconcentrated to less than one half of the collected volume using arotary evaporator and water bath heated to 45° C. The concentrate wasdiluted with an equal volume of brine and then made basic (pH 10) with20 mL of 10% aqueous sodium carbonate solution. The product wasextracted with 4×25 mL of chloroform. The combined extracts were washedwith 30 mL of water, dried over anhydrous sodium sulfate, filtered andconcentrated to dryness under reduced pressure. After vacuum drying, theresidue was dissolved in 2 mL of acetonitrile and treated with 50 mg ofsodium bicarbonate. After the mixture was stirred for 15 min, it wasfiltered and the filtrate was concentrated to dryness under a stream ofnitrogen. The title compound (30.3 mg) was obtained after vacuum drying;FAB MS M/Z: 717 (M+H)⁺ ; IR (0.15% in CCl₄) 3560. 3470, 3440, 3345 and1660 cm⁻¹.

EXAMPLE 10 Reaction of[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-onewith Aqueous Acetic Acid

To[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(di-methylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(515 mg, 0.72 mmol), the product of example 1, suspended in 20 mL ofwater, was added 20 mL of glacial acetic acid. The reaction mixture wasstirred at ambient temperature for approximately 4 hours and then pouredinto 300 mL of water. The solution was made basic (pH 8-9) by adding 5%sodium bicarbonate solution and ammonium hydroxide and gently swirling.The aqueous solution was poured into a separatory funnel containingmethylene chloride and the methylene chloride layer was separated. Theaqueous layer was extracted with 3×100 mL of methylene chloride. Thecombined methylene chloride extracts were concentrated under reducedpressure to give 300 mg of the acid degradation products. One of thoseproducts was identified as the corresponding anhydro compound,[1R-(1R*,2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*,14R*)]-9-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3-hydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethyl-amino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15,16-dioxatricyclo[10.2.1.1¹,4]pentadecan-7-one. A crude sample of the anhydro compound (540 mg) waschromatographed on silica gel (approximately 100 g) equilibrated withchloroform/acetonitrile/methanol/ammonia (10:3:0.4:0.03) and eluted withchloroform/acetonitrile/methanol/ammonia (10:3:0.6:0.006) to give 100 mgof the anhydro compound. FAB MS M/Z: 715 (M+H)⁺ ; IR (0.15% in CCl₄)3460, 3435, 3330 and 1645 cm⁻¹ ; ¹³ C NMR (DMSO-d6) C9 at 114.3 ppm.[α]_(D) ²³ =-11.8° (c 1.00; MeOH). A sample was crystallized fromacetonitrile, m.p. 178°-182° C.

EXAMPLE 11 Reaction of[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-onewith Aqueous Hydrochloric Acid

[2R-(2R*,3R*,4R*5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one(874 mg, 1.22 mmol), the product of example 1, was dissolved inacetonitrile and the solution was concentrated down to a foam underreduced pressure. Water (50 mL) was added to the foam while the sides ofthe flask were scraped. A solution of 2 mL of 1N aqueous hydrochloricacid in 100 mL of water was prepared and 39.33 mL of this solution wasadded portionwise to the aqueous erythromycin A lactam enol ether. Afterthe addition was complete the pH of the resultant solution was 3. Assample dissolved it was necessary to adjust the pH by the addition of 1Naqueous hydrochloric acid in order to maintain the pH at approximately2.5 . After stirring for 90 minutes the reaction mixture was quenched bypouring the acidic solution into a separatory funnel with 100 mL of 5%aqueous sodium bicarbonate solution and 3 mL of concentrated ammoniumhydroxide. The aqueous layer was extracted with 3×50 mL of methylenechloride. The organic layer was washed with brine, dried over anhydroussodium sulfate, filtered and concentrated under reduced pressure. Silicagel (approximately 100 g) was slurried with acetonitrile/ammonia(10:0.5) and poured into a column. The column was equilibrated with 2 Lof chloroform/acetonitrile/methanol/ammonia (10:3:0.5:0.05). The residuewas loaded on the column and the column was eluted withchloroform/acetonitirile/methanol/ammonia (10:0.3:0.5:0.05) to give 160mg of[3R-(3R*,4S*,5S*,6R*,7R*,9S*,11R*,12R*,13R*,14R*)]-4-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-14-ethyl-7,12,13-trihydroxy-3,5,7,9,11,13-hexamethyl-6-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]aza-cyclotetradecane-2,10-dione("erythromycin A lactam"). FAB MS M/Z: 733 (M+ H)⁺ ; IR (0.15% in CCl₄)3560, 3430, 1675 and 1655 cm⁻¹ ; ¹³ C NMR (DMSO-d6) C9 at 217.2 and107.6 (mixture of ketone and 9,12-hemiacetal). [α]_(D) ²³ =-52.9° (c1.00; MeOH).

EXAMPLE 12[2R-(2R*,3R*,4R*,5R*,8R*,9R*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,6,8,10,12,14-heptamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

A solution of 15% methylamine in methanol was prepared by adding 15 mLof liquid methylamine in 85 mL of methanol cooled to 0° C. in an icebath.[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylohexo-pyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5one(441.6 mg, 0.6327 mmol), from Step 4 of Example 1, was dissolved in 10mL of the methylamine solution in a 20 mL heavy-walled reaction tube.The reaction tube was sealed with a teflon screw cap and "O" ring andthen the tube was heated at 100° C. in an oil bath for 5 days. Thereaction mixture was sampled and analyzed using the HPLC systemdescribed in Step 3 of Example 1 A. According to HPLC analysis, theepoxide starting material was consumed. The crude reaction material wasdiluted with 100 mL of 8% aqueous sodium bicarbonate solution andextracted with 3×25 mL of chloroform. The chloroform extract was washedwith 50 mL of a 1:1 solution of 8% aqueous sodium bicarbonate and brine.The chloroform solution was dried over anhydrous sodium sulfate,filtered and concentrated in vacuo. The residue was dissolved in 30 mLof acetonitrile and the solvent removed in vacuo to give a dark yellowresidue. The residue (430 mg) was chromatographed on 50 g of silica gelwhich had been equilibrated withchloroform/acetonitrile/methanol/ammonium hydroxide (87.8:10:2:0.2v/v/v/v), eluting at 2.1 mL/min with the same solvent used forequilibration followed, after collecting sixty five 15 mL fractions, bychloroform/acetonitrile/methanol/ammonium hydroxide (83.6:10:6:0.4v/v/v/v) to give 275.2 mg (60% yield) of the title compound; DCl/NH₃M/Z: 729 (M+H)⁺ ; IR (0.15% in CCl₄) 3560, 3510, 3460, 1700 and 1625 MScm⁻¹. [α]_(D) 22° C.=-58.7° (c 1.00; MeOH).

EXAMPLE 13 Alternate preparation of[2R-[2R*,3R*(1R*,2R*),6R*,7S*,8S*,9S*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-dihydroxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

Erythromycin A (30.01 g, 40.89 mmol) was suspended in 200 mL ofacetonitrile. To the stirred suspension was added 10.541 g (81.751 mmol)of dichloroacetic acid in 100 mL of acetonitrile over a 20 minuteperiod; the erythromycin dissolved after addition of about half thevolume. The reaction was stirred for 2.5 hours at 23° C. giving the enolether. To the solution containing the enol ether intermediate was addedover a 30 minute period a solution of 16.951 g (122.65 mmol) ofpotassium carbonate dissolved in 300 mL of 1:1 (v/v) methanol: water.The mixture was then refluxed for 1.5 hours, cooled to room temperatureand concentrated in vacuo to leave a white residue. The residue wasdissolved in a mixture of 200 mL of chloroform, 200 mL of 8% sodiumbicarbonate solution and 100 mL of saturated brine. The organic layerwas then separated, the aqueous layer extracted with chloroform and theorganic layers combined. This solution was washed with a mixture ofsodium bicarbonate solution and saturated brine, dried over sodiumsulfate, filtered and concentrated to dryness. The residue was dissolvedin 100 mL of acetonitrile and evaporated in vacuo to give 28.67 g ofcrude product as a foam. The material was crystallized from acetonitrileto afford 18.717 g of the title product. A second extraction wasperformed, and the total yield for the reaction found to be 69%.

EXAMPLE 14[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,4,6-Trideoxy-3-C-methyl-3O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[2-O-acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

Step 1.[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[2-O-acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

A 3.001 g (4.300 mmol)) sample of[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one(the product of Example 1A, step 2 above) was dissolved in 40 mL ofmethylene chloride, and 1.2 mL of triethyl amine and 0.81 mL of aceticanhydride were added. The reaction was allowed to proceed for 24 hours,whereupon the solvent was removed under vacuum and the residue dissolvedin 100 mL of ethyl acetate. The ethyl acetate solution was washed with8% NaHCO₃, 5% NaH₂ PO₄, H₂ O and 8% NaHCO₃ solutions, then dried oversodium sulfate, filtered and taken to dryness. Exhaustive drying yielded3.175 g of the title product. This material was taken to the next stepwithout further purification.

Step 2.[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-4-O-imidazolylthiocarbonyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[2-O-acetyl-3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

A 3.109 g sample of the product of Step 1 above, 2.064 g (16.894 mmol)of DMAP and 2.260 g (12.681 mmol) of 1,1'-thiocarbonyldiimidazole(Aldrich) were dissolved in 40 mL of methylene chloride, and thereaction allowed to proceed at 25° C. for 18 hours. To the reactionmixture was then added 1.15 mL of concentrated NH₄ OH, and the reactionstirred at room temperature for 45 minutes. Next was added 100 mL of0.5M acetate buffer, followed by 2 mL of acetic acid to adjust the pH to6.0, and the mixture stirred for 2 hours. Additional solvent was added,and the organic phase separated. After washing first with acetate buffer(pH 4.7), and then with 8% NaHCO₃, the solution was dried over sodiumsulfate, filtered and taken to dryness to yield 3.357 g of the titlecompound.

Step 3.[2R-[2R*,3R*(1R*,2S*),6R*,7S*,8S*,9R*,10R*]]-7-[(2,4,6-Trideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-3-(1,2-epoxy-1-methylbutyl)-2,6,8,10,12-pentamethyl-9-[[2-O-acetyl-3,4,6-trideoxy-3-(dimethylamino)-.beta.-D-xylo-hexopyranosyl]oxy]-4,13-dioxabicyclo[8.2.1]tridec-12-en-5-one

A mixture of 3.319 g (3.905 mmol) of the product of step 2 above and0.128 g (0.779 mmol) of AIBN (2,2'-azobis(2-methylpropionitrile) wasdissolved in 60 mL of dry toluene. To this was added 2.2 mL (6.98 mmol)of tri-n-butyl tin hydride, and the mixture degassed and held under N₂before heating in an oil bath at 100° C. for 1 hour. The mixture wasconcentrated to a syrup, then dissolved in 100 mL of CHCl₃. Thissolution was washed with acetate buffer (pH 4.7), then with 8% aqueousNaHCO₃, dried over Na₂ SO₄, filtered and taken to dryness to yield 5.653g of a residue. The residue was dissolved in 200 mL of acetonitrile andwashed 3 times with 50 mL portions of hexane. The acetonitrile layer wasconcentrated to dryness to afford 2.69 g of the title product.

EXAMPLE 15 [2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,4,6-Trideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

A 508 mg sample of the product of Example 14 was placed in a 20 mLpressure tube. The sample was dissolved in 10 mL of 15% NH₃ in methanol,flushed with N₂, sealed and heated at 100° C. in an oil bath for 4 days.The contents of the tube were taken to dryness, and the crude productpurified by preparative chromatography on silica gel, eluting with0.2:2:10:100 NH₄ OH:methanol:acetonitrile:CHCl₃. The solvent was removedfrom the fractions containing the product to afford 228 mg of the titlecompound as a glass. MS M/Z 699 (M+H). IR (CCl₄): 3520b, 3480b, 3440sh,3355sh, 1700w, 1662s. [α]_(D) =-33.6° (c=0.50, MeOH, 24° C.). Anal Calc.for C₃₇ H₆₆ N₂ O₁₀ : C, 63.58; H, 9.52; N, 4.01; Found: C, 63.15; H,9.48 ; N, 3.98.

EXAMPLE 16[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,4,6-Trideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,6,8,10,12,14-heptamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

A 607.2 mg sample of the product of Example 14 was placed in a 20 mLpressure tube, and 10 mL of 15% methylamine in methanol was added. Thetube was flushed with N₂, sealed and heated at 100° C. in an oil bathfor 4 days. The tube was opened, and the solvent removed to yield 634 mgof crude product. This material was purified by chromatography on silicagel, eluting with 0.2:2:10:100 NH₄ OH:methanol:acetonitrile:CHCl₃. Thesolvent was removed from the fractions containing the product to afford302.4 mg of the title compound as a glass. [α]_(D) =-55.0° (c=1.00,MeOH, 29° C.). IR (CCl₄): 3510b, 3460b, 1700w, 1622s cm⁻¹. Anal Calc.for C₃₈ H₆₈ N₂ O₁₀ : C, 64.02; H, 9.61; N, 3.93; Found: C, 64.02; H,9.67; N, 3.92.

EXAMPLE 17[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(n-butylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

To a heavy-walled flask (Parr Instrument Co.) were added 311 mg of theproduct of Example 4, 30 mL of methanol, 120 mg of 10% Pd/C and 0.30 mLof butyraldehyde. The flask was charged with 4 atm of hydrogen andshaken for 16 hours. The catalyst was removed by filtration, and thesolvent was removed under vacuum. The residue was dissolved inacetonitrile and taken to dryness twice to give 340 mg of crude product.The crude product was purified by reverse phase HPLC, eluting with 40:60acetonitrile:water containing 10 g/L of ammonium acetate. The eluentfractions were concentrated to half their volume and were made alkalineby the addition of 1N NaOH in small portions. The product was extractedinto chloroform which was washed with 8% aqueous NaHCO₃, dried oversodium sulfate, filtered and concentrated. The residue was dissolved inacetonitrile which was then removed under vacuum to yield 170.6 mg ofthe title product as a glass. MS M/Z 757 (M+H). [α]D=-32.9° (c=1.00,methanol, 28° C.). IR (CCl₄): 3560, 3520, 3440, 1702, 1660 cm⁻¹. AnalCalc. for C₄₀ H₇₂ N₂ O₁₁ : C, 63.46; H, 9.59; N, 3.70; Found: C, 62.95;H, 9.48; N, 3.63.

EXAMPLE 18[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(n-propylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

By a procedure similar to that described in Example 17, 382 mg of theproduct of Example 4 was reacted with propionaldehyde instead ofbutyraldehyde, to afford 196.2 mg of the title compound as a whiteglass. MS M/Z 743 (M+H). [α]D=-32.8° (c=1.00, methanol, 28° C.). AnalCalc. for C₃₉ H₇₀ N₂ O₁₁ : C, 63.05; H, 9.50; N, 3.79; Found: C, 63.05;H, 9.50; N, 3.79.

EXAMPLE 19[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(i-propylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

In a 20 mL pressure tube were placed 200 mg of the product of Example 4,0.5 mL of diisopropylethylamine, 1.0 mL of 2-iodopropane and 2.0 mL ofacetonitrile. The tube was flushed with N₂, sealed and heated at 70° C.in an oil bath. For workup, the products of two such runs were combined.The solvents were remove, and the residue was dissolved in a mixture of30 mL ethyl acetate, 20 mL of 8% aqueous NaHCO₃ and 100 mg of sodiumthiosulfate. The organic layer was washed, dried and filtered, to give354 mg of crude product. The crude product was purified by HPLC by aprocedure similar to that described in Example 19 to afford 196.2 mg ofthe title compound as a white glass. MS M/Z 781 (M+H). [α]D=-32.8°(c=1.00, methanol, 27° C.). Anal Calc. for C₃₉ H₇₀ N₂ O₁₁ : C, 63.05; H,9.50; N, 3.79; Found: C, 62.54; H, 9.50; N, 3.77.

EXAMPLE 20[2R-(2R*,3R*,4R*,5R*,8R*,9S*,10S*,11R*,12R*)]-9-[(2,6-Dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl)oxy]-5-ethyl-3,4-dihydroxy-2,4,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(i-butylmethylamino)-β-D-xylo-hexopyranosyl]oxy]-6-aza-15-oxabicyclo[10.2.1]pentadec-14-en-7-one

By a procedure similar to that described in Example 19, 400 mg of theproduct of Example 4 were reacted with 2-iodobutane instead of2-iodopropane to afford, after purification by HPLC, two samples (theN-(S)-2-butyl and N-(R)-2-butyl isomers).

21a. (S-isomer): 134 mg; MS M/Z 757 (M+H). [α]D=-30.2° (c=0.5, methanol,27° C.). IR 3560, 3440, 3350, 1700, 1658 cm⁻¹.

21b. (R-isomer): 112.5 mg; MS M/Z 757 (M+H). [α]_(D) =-36.4° (c=0.5,methanol, 27° C.). IR 3560, 3440, 3350, 1700, 1659 cm⁻¹.

EXAMPLE 21 In Vitro Assay of Gastric Prokinetic Activity

The compounds of the present invention were tested in vitro for theirability to induce contraction of smooth muscle strips isolated fromrabbit small intestine using the following procedure.

Rabbits were sacrificed and 15 cm of duodenum was rapidly removed andplaced in ice-cold modified Ringers solution (120 mM sodium chloride, 25mM sodium bicarbonate, 4.7 mM potassium chloride, 1.25 mM calciumchloride, 1.20 mM magnesium sulfate and 5.6 mM glucose). Thelongitudinal muscle layer was separated from the circular muscle byblunt dissection and cut into strips of 10×20 mm. Double-folded stripswere vertically suspended between two hooks in 10 mL tissue baths with amechanical preload of 1 g. The upper hook was connected to an isotonicforce transducer, and its displacement was recorded on a Grasspolygraph. The tissue baths contained modified Ringers solution at 37°C. and were continuously gassed with 95% oxygen/5% carbon dioxide inorder to maintain the pH at 7.5.

After a stabilization period of at least 60 minutes, a contractilitydose-response series was performed by adding increasing finalconcentrations of methacholine (10⁻⁷ M, 10⁻⁶ M and 10⁻⁵ M) in volumes of100 μL. The bath solutions were replaced at least three times betweendoses.

After the methacholine dose-response series was completed, a testcompound dose response curve was initiated by the same procedure usedfor the methacholine dose-response series, with at least fiveconcentrations of test compound within the range of 10⁻¹⁰ M to 10⁻⁴ M.The tissues were washed repeatedly between doses, and the studies werecompleted by recording the contractile response to 10⁻⁵ M methacholineto ascertain integrity of the muscle preparation. Contractile responseswere expressed as percent of maximal contraction. The concentration oftest compound which produces half of the maximal contraction (ED₅₀value) and the negative logarithm of the ED₅₀ value (pED₅₀) wereestimated from the dose-response curves. The pED₅₀ values are shown inTable 1 in comparison to erythromycin A which is a knowngastrointestinal prokinetic agent. From these data it is evident thatthe compounds of the present invention are potent prokinetic agents.

                  TABLE 1                                                         ______________________________________                                        In Vitro Rabbit Duodenal Smooth Muscle Contraction Assay                      Example Number                                                                             pED.sub.50 (-log M)                                                                        Relative Potency                                    ______________________________________                                         1           7.10         18.0                                                 3           7.50         45.0                                                 4           6.50         5.0                                                  5           7.10         18.0                                                 7           6.60         5.6                                                  8           6.30         3.0                                                  9           6.25         2.5                                                 10           6.10         1.8                                                 12           7.22         23.4                                                15           8.27         263                                                 16           8.50         447                                                 17           5.67         0.66                                                18           6.00         1.41                                                19           7.63         60.3                                                   20 (S)    8.40         355                                                    20 (R)    9.27         2630                                                erythromycin A                                                                             5.85         1.0                                                 ______________________________________                                    

EXAMPLE 22 Gastrointestinal Prokinetic Activity: In Vivo Assay inAnesthetized Dogs

The compounds of the present invention were tested in vivo for theirability to induce gastrointestinal motility using the followingprocedure: Adult female beagle dogs, food deprived for 16-20 hours andweighing between 7.0 and 12.0 kg, were anesthetized with 30 mg/kg ofsodium pentobarbital given intravenously. Anesthesia was maintainedduring the experimental procedure by continuous intravenous infusion of5 mg/kg Nembutal in 0.9% saline. After tracheal intubation, the animalswere mechanically respired with a Harvard positive pressure respiratorypump. Rectal temperature was maintained at 37° C. by a heated animaltable. A polyethylene catheter was inserted into the right femoralartery to record blood pressure and heart rate using a Steatham P23pressure transducer. Polyethylene catheters were also introduced intothe right femoral vein for infusion of anesthetic and the left femoralvein for drug administration and blood samples. The abdomen was openedby a midline incision immediately below the xiphoid process extending to2 cm below the umbilicus.

Five strain-gauge transducers were used to monitor contractile activityof the circular muscle layer of the stomach or intestine. Each wascalibrated to give a 60% full scale deflection when supporting a 100 gweight between two planar surfaces. However, due to variability intransducer response, output when applied to the circular muscle layerwas observed to vary despite the first stage of calibration. Therefore,final sensitivity adjustments were subsequently made with transducerssewn in place to yield comparable deflections of paired transducers. Twotransducers were sutured to the serosal surface of the antrum of thestomach. The first was approximately 5 cm proximal to the pylorus andthe second 1 cm proximal to the first. Two transducers were also suturedto the duodenum; they were approximately 12 cm distal to the pylorus andabout 1 cm apart. Only one transducer was sutured to the jejunum,approximately 10 cm from the ligament of Treitz, and was not paircalibrated. Two transducers were used in both the stomach and duodenumto minimize variability. After application of the transducers, theabdominal wound was closed and gastrointestinal motility patterns wereallowed to stabilize for from 45 to 90 minutes before drugadministration.

Motility and blood pressure were recorded by a Grass Model 7oscillograph. The records were manually analyzed by a scoring systemwhich included both magnitude and duration of muscular contractions. Themanual scoring system consisted of pulse-height measurement by countingrecorded contractile waves in relation to five selected amplitudes (7,17, 34, 68, 136, >136 g). A transparent guide was used to facilitatescoring. A minimal pulse-height score was assigned for every contractionbetween each of these levels (a score of 0.5 for all contractionsbetween 7 and 17 g, a score of 1.0 for contractions between 17 and 34 g,a score of 2.0 for contractions between 34 and 68 g, a score of 4.0 forcontractions between 68 and 136 g and a score of 8.0 for contractionsover 136 g). Scores were computed for the 60 minute period followingdrug administration. Mean scores were computed for the two transducersin both stomach and duodenum. Drugs were administered for either 2 or 3periods, each period consisting of 90 minutes. In period 1, the testcompound was typically administered and motility responses recorded for60 minutes. In period 2, erythromycin A lactobionate was thenadministered to establish an internal control for each animal studied.All compounds for one experiment were given at the same dose, usually4.0 mg/kg.

Several experiments were done with erythromycin A lactobionate alone.Erythromycin was administered in both periods and the data analyzed inthe standard manner. Due to dose-dependent tachyphlaxis, a motilityresponse induced by erythromycin in period 1 resulted in reducederythromycin response in period 2. Test compounds should ideally beinvestigated by both prior and subsequent administration with respect toerythromycin dosing to minimize tachyphylactic bias. For initialscreening, however, the standard protocol was test compound (period 1)followed by erythromycin (period 2).

The final expression of results was a ratio between the motility scoringfor the test compound (period 1) and erythromycin A lactobionate (period2). For stomach, duodenum and jejunum, the motility score in response tothe test compound was divided by the motility score for erythromycin.From these three ratios, an arithmetic mean ratio for "overall motilityindex" was calculated in which contributions from the three tissue areasmeasured were weighted equally. The compound of Example 1, when testedin vivo as described above, exhibited a motility index of 19.9 comparedto erythromycin A, which was assigned a motility index of 1,demonstrating that the compounds of the invention exhibit potentgastrointestinal prokinetic activity in vivo.

We claim:
 1. A process for preparing a compound according to claim 1wherein A is a group of the formula ##STR11## comprising the step oftreating an amine alcohol having the formula ##STR12## with a suitablebase under conditions sufficient to induce cyclization to a lactam.
 2. Aprocess for preparing a compound according to claim 1 wherein A is agroup of the formula ##STR13## and R⁶ is --OH, comprising the step oftreating an epoxide having the formula ##STR14## with an amine underconditions sufficient to induce epoxide opening and spontaneouscyclization to a lactam.